Massachusetts utilities sign 4.5 GWh storage contracts
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- Eversource Energy, National Grid, and Unitil filed long-term contracts with developers of three utility-scale battery storage projects totaling 1,068 MW/4,472 MWh, slated to come online by 2030 and provide clean peaking capacity in Greater Boston and southeastern Massachusetts.
- The three projects comprise Jupiter Power's 700 MW/2,800 MWh Trimount installation and two Flatiron Energy projects — the 250 MW/1,000 MWh Energizar and the 168 MW/672 MWh Salt Cod.
- The agreements advance Massachusetts's effort to deploy 5 GW of energy storage by 2030, complementing Gov. Maura Healey's earlier announcement of plans to procure an additional 5 GW by 2035 as part of a broader 15 GW non-emitting capacity target.
- Trimount, expected to be New England's largest energy storage installation, will occupy 20 acres at a former oil terminal in Everett, connecting at the nearby Mystic substation, with capacity split between Unitil's Fitchburg Gas & Electric Light subsidiary (200 MW) and National Grid's Massachusetts affiliates (500 MW).
- Flatiron expects Energizar to begin operations in Q2 2027 from a former industrial site in Chelsea, while Salt Cod targets late 2028 on 11 acres at the shuttered Montaup Power Plant site in Somerset — a location where an Italian subsea cable plant was canceled last year amid the Trump administration's crackdown on offshore wind.
- Financial analyses filed with the Massachusetts Department of Public Utilities project modest reductions to most customers' monthly electricity bills over the next 5 to 15 years.
- A fourth project — Rhynland Energy's 200 MW River Mill Storage — emerged from the same solicitation but has not yet signed a long-term contract; Rhynland did not respond to a request for comment from Utility Dive.
Why it matters: Massachusetts ratepayers stand to see modest monthly bill reductions over 5 to 15 years, while the contracts advance the state's 5 GW storage target by 2030. Trimount's 700 MW — set to be New England's largest battery installation — converts a former Everett oil terminal into a grid-flexibility asset.
